An ink cartridge detachably attachable to an apparatus for recording an image on a sheet is known in the art. One such ink cartridge includes an ink storage chamber for storing therein ink.
As described in Japanese Patent Application Publication No. 2003-237102, in most of the ink cartridge, the ink storage chamber is open to an atmosphere when the ink cartridge is in use. With this configuration, a pressure in the ink storage chamber is maintained at an atmospheric pressure.
Further, as described in Japanese Patent Application Publication No. 2004-90624, communication between the ink storage chamber and an outside is blocked when the ink cartridge is not attached to the apparatus. This configuration prevents ink stored in the ink storage chamber from leaking out of the ink cartridge. On the other hand, the ink storage chamber is open to an atmosphere when the ink cartridge has been attached to the apparatus. Thus, a pressure in the ink storage chamber is maintained at an atmospheric pressure.
The ink cartridge disclosed in Japanese Patent Application Publication No. 2004-90624 is provided with a valve body movable to perform switching between a communicating state between the ink storage chamber and the atmosphere and a non-communicating state therebetween. The valve body is positioned by an urging force of a leaf spring to close a communication hole adapted to connect the ink storage chamber to an outside when the ink cartridge is not attached to the apparatus. On the other hand, the valve body is moved by a protrusion provided in the apparatus against the urging force of the leaf spring to open the communication hole during an attachment process of the ink cartridge to the apparatus.